1/*
2 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
3 * Collects data related to memory management.
4 *
5 * Copyright IBM Corp. 2003, 2006
6 *
7 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
8 */
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <linux/kernel_stat.h>
14#include <linux/pagemap.h>
15#include <linux/swap.h>
16#include <linux/slab.h>
17#include <asm/io.h>
18
19#include "appldata.h"
20
21
22#define P2K(x) ((x) << (PAGE_SHIFT - 10))	/* Converts #Pages to KB */
23
24/*
25 * Memory data
26 *
27 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
28 * the structure version (product ID, see appldata_base.c) needs to be changed
29 * as well and all documentation and z/VM applications using it must be
30 * updated.
31 *
32 * The record layout is documented in the Linux for zSeries Device Drivers
33 * book:
34 * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
35 */
36struct appldata_mem_data {
37	u64 timestamp;
38	u32 sync_count_1;       /* after VM collected the record data, */
39	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
40				   same. If not, the record has been updated on
41				   the Linux side while VM was collecting the
42				   (possibly corrupt) data */
43
44	u64 pgpgin;		/* data read from disk  */
45	u64 pgpgout;		/* data written to disk */
46	u64 pswpin;		/* pages swapped in  */
47	u64 pswpout;		/* pages swapped out */
48
49	u64 sharedram;		/* sharedram is currently set to 0 */
50
51	u64 totalram;		/* total main memory size */
52	u64 freeram;		/* free main memory size  */
53	u64 totalhigh;		/* total high memory size */
54	u64 freehigh;		/* free high memory size  */
55
56	u64 bufferram;		/* memory reserved for buffers, free cache */
57	u64 cached;		/* size of (used) cache, w/o buffers */
58	u64 totalswap;		/* total swap space size */
59	u64 freeswap;		/* free swap space */
60
61// New in 2.6 -->
62	u64 pgalloc;		/* page allocations */
63	u64 pgfault;		/* page faults (major+minor) */
64	u64 pgmajfault;		/* page faults (major only) */
65// <-- New in 2.6
66
67} __packed;
68
69
70/*
71 * appldata_get_mem_data()
72 *
73 * gather memory data
74 */
75static void appldata_get_mem_data(void *data)
76{
77	/*
78	 * don't put large structures on the stack, we are
79	 * serialized through the appldata_ops_mutex and can use static
80	 */
81	static struct sysinfo val;
82	unsigned long ev[NR_VM_EVENT_ITEMS];
83	struct appldata_mem_data *mem_data;
84
85	mem_data = data;
86	mem_data->sync_count_1++;
87
88	all_vm_events(ev);
89	mem_data->pgpgin     = ev[PGPGIN] >> 1;
90	mem_data->pgpgout    = ev[PGPGOUT] >> 1;
91	mem_data->pswpin     = ev[PSWPIN];
92	mem_data->pswpout    = ev[PSWPOUT];
93	mem_data->pgalloc    = ev[PGALLOC_NORMAL];
94	mem_data->pgalloc    += ev[PGALLOC_DMA];
95	mem_data->pgfault    = ev[PGFAULT];
96	mem_data->pgmajfault = ev[PGMAJFAULT];
97
98	si_meminfo(&val);
99	mem_data->sharedram = val.sharedram;
100	mem_data->totalram  = P2K(val.totalram);
101	mem_data->freeram   = P2K(val.freeram);
102	mem_data->totalhigh = P2K(val.totalhigh);
103	mem_data->freehigh  = P2K(val.freehigh);
104	mem_data->bufferram = P2K(val.bufferram);
105	mem_data->cached    = P2K(global_page_state(NR_FILE_PAGES)
106				- val.bufferram);
107
108	si_swapinfo(&val);
109	mem_data->totalswap = P2K(val.totalswap);
110	mem_data->freeswap  = P2K(val.freeswap);
111
112	mem_data->timestamp = get_tod_clock();
113	mem_data->sync_count_2++;
114}
115
116
117static struct appldata_ops ops = {
118	.name      = "mem",
119	.record_nr = APPLDATA_RECORD_MEM_ID,
120	.size	   = sizeof(struct appldata_mem_data),
121	.callback  = &appldata_get_mem_data,
122	.owner     = THIS_MODULE,
123	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
124};
125
126
127/*
128 * appldata_mem_init()
129 *
130 * init_data, register ops
131 */
132static int __init appldata_mem_init(void)
133{
134	int ret;
135
136	ops.data = kzalloc(sizeof(struct appldata_mem_data), GFP_KERNEL);
137	if (!ops.data)
138		return -ENOMEM;
139
140	ret = appldata_register_ops(&ops);
141	if (ret)
142		kfree(ops.data);
143
144	return ret;
145}
146
147/*
148 * appldata_mem_exit()
149 *
150 * unregister ops
151 */
152static void __exit appldata_mem_exit(void)
153{
154	appldata_unregister_ops(&ops);
155	kfree(ops.data);
156}
157
158
159module_init(appldata_mem_init);
160module_exit(appldata_mem_exit);
161
162MODULE_LICENSE("GPL");
163MODULE_AUTHOR("Gerald Schaefer");
164MODULE_DESCRIPTION("Linux-VM Monitor Stream, MEMORY statistics");
165